#AskGlaston Episode 49: Do we get the same internal strength after glass cutting as without it?

Do we get the same internal glass strength after glass cutting as without it?

We have done some experiments on the heat-strengthened glass. After heat treatment, we have cut the glass with a water jet without any breakage. Then, we have done some break tests on them, and all of the break patterns have been normal as compared to heat-treated glass without cutting.After cutting, will we get the same internal glass strength as without cutting?

Thank you for your question. It is interesting to hear that you have been able to cut a heat-strengthened glass with a water jet. The common thought is that it is not possible to cut heat-strengthened glass because during the cutting, the cut edge is getting into a tensile zone, and that breaks the glass.

But what you have asked is whether the strength can remain as good as before. It is possible that it is! This is because the cutting process changes only the stresses around the edges. And it only affects as much of the glass length from the edge, as the edge thickness of this glass. This is where that glass stress profile changes.

But of course, it might also be so that there still is a small change in the overall strength of glass because the glass edge work becomes different compared to what it was before.